The Basics of a Car
A car (also called automobile or motorcar) is a wheeled vehicle designed to transport people. Most cars use an internal combustion engine as a power source and are controlled by a driver. Cars come in a variety of models, shapes and sizes. They can be divided into categories based on their body style, such as sedans, coupes and minivans, or by how they are used, such as sports or family cars. Most vehicles have four wheels and seat one to eight people. Some cars are powered by electric motors rather than engines.
Cars help millions of people around the world get to where they want to go quickly and comfortably. They also provide jobs in factories that make them and at gas stations, restaurants and motels where travelers stop. But cars are expensive to buy, maintain and operate. And they can cause problems such as accidents, air pollution and parking space shortages in cities.
The basic building blocks of the modern car date back several hundred years. In the late 1600s, Dutch scientist Christiaan Huygens invented a type of piston engine that used gunpowder to create a spark. This invention was an important step in the development of the modern car.
In the 19th century, steam-powered road vehicles such as phaetons and steam buses became popular in Europe. They could travel fast but were difficult to start and had a limited range. In the early 1900s, gas-powered automobiles gained popularity in the United States. In the 1930s and 1940s, automakers introduced many new features to improve comfort and safety for their customers. These included power steering and brakes, automatic controls and electrical systems.
Most cars today are powered by a four-stroke or V-8 gasoline engine. This engine uses fuel, usually petrol or diesel, to burn inside cylinders that expand as they heat up. A spark plug ignites the gases and creates electricity that moves a crankshaft that turns the wheels of the car. The engine delivers power through a transmission, a drive shaft and differential to the drive wheels. The drive wheels can be located in the front or the back of the car. Cars that need to drive on uneven or snowy ground often have four-wheel drives.
The braking system slows the car when needed by pressing a friction pad against a drum or disc with the help of a hydraulic system. The suspension system holds the weight of the car and provides a smooth ride by using springs, axles and tires that grip the road. Cars are also equipped with a heating and cooling system that keeps the passengers comfortable. Safety features include seat belts, air bags and child seats.